更多"Which two statements about views ar"的相关试题:
[多项选择]Which two statements about views are true? ()
A. A view can be created as read only.
B. A view can be created as a join on two or more tables.
C. A view cannot have an ORDER BY clause in the SELECT statement.
D. A view cannot be created with a GROUP BY clause in the SELECT statement.
E. A view must have aliases defined for the column names in the SELECT statement.
[多项选择]Which two statements about sequences are true?()
A. You use a NEXTVAL pseudo column to look at the next possible value that would be generated from a sequence, without actually retrieving the value.
B. You use a CURRVAL pseudo column to look at the current value just generated from a sequence, without affecting the further values to be generated from the sequence.
C. You use a NEXTVAL pseudo column to obtain the next possible value from a sequence by actually retrieving the value from the sequence.
D. You use a CURRVAL pseudo column to generate a value from a sequence that would be used for a specified database column.
E. If a sequence starting from a value 100 and incremented by 1 is used by more then one application, then all of these applications could have a value of 105 assigned to their column whose value is being generated by the sequence.
F. You use REUSE clause when creating a sequence to restart the sequence once it generates the maximum value defined for the sequence.
[多项选择]Which two statements about subqueries are true?()
A. A single row subquery can retrieve data from only one table.
B. A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.
C. A SQL query statement can display data from table B that is referred to in its subquery, without including table B in its own FROM clause.
D. A single row subquery can retrieve data from more than one table.
E. A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.
F. A multiple-row subquery cannot be used in a condition where the LIKE operator is used for comparison.
[多项选择]Which two statements are true about precedence values in policy?() (Choose two.)
A. 1 is the default precedence.
B. A lower number is preferred.
C. A higher number is preferred.
D. 100 is the default precedence.
[多项选择]Which two statements are true about static routes in the Junos OS?()
A. Static routes are defined at the [edit routing-instances] hierarchy.
B. Static routes must have a next hop defined.
C. Static routes remain in the routing table until you remove them or until they become inactive.
D. Static routes are learned by neighboring devices and added to their routing tables.
[多项选择]Which two statements are true about the duplexing of the backups taken by RMAN? ()(Choose two.)
A. It's only supported for the backups performed on the tape
B. It is not supported for backup operations that produce image copies
C. Duplex backups need a parallelism for the device to be equal to number of copies
D. Duplex backups can be performed to either disk or tape, but cannot be performed on tape and disk simultaneously
[多项选择]Which two statements are true about the forwarding table?()
A. The forwarding table lists each source protocol and preference for each destination.
B. The forwarding table contains only active routes.
C. The forwarding table is used to process transit packets.
D. The forwarding table is stored in compact flash